DS-guided deposition of PEDOT onto silk fabrics for rapid photothermal antibacterial and respiratory sensing

Polystyrene sulfonic acid is widely utilized as an effective template for synthesis of poly (3,4-ethylenedioxythiophene) (PEDOT), but the bonding fastness between PEDOT and textiles is unsatisfactory, which easily leads to poor conductivity. In this study, a linear template of dextran sulfate (DS) was covalently grafted onto silk fibers (SF), followed by in-situ deposition of PEDOT onto the silk fabrics, aiming at constructing a functional silk fabric with rapid photothermal antibacterial ability and durable flexible sensing performance. Impressively, the composite fabric of SF-g-DS/PEDOT exhibits excellent photothermal conversion performance and can rise to 80 °C within 1 min of irradiation with the light intensity of 100 mW/cm 2 , and can kill 99.99% of Escherichia coli ( E. coli ) on the fabric surface. Benefited from the strong interaction forces between the conductive polymer and silk fibers, the SF-g-DS/PEDOT fabric can still reach 75 °C after 15 times of washing, and achieves a 99.4% bactericidal rate against E. coli . In a relatively weak winter sunlight, the surface temperature of SF-g-DS/PEDOT can also be raised to 45 °C to keep the human body warm. Meanwhile, the excellent conductivity of the deposited PEDOT endows the composite with antistatic performance, accurate flexible strain and respiratory sensing behaviors, companying with encouraging UV resistance. The present work provides a feasible alternative for development of photothermal antibacterial, lightweight warm clothing and smart wearable textiles.